Acoustic Emission Characteristics of Mode I Delamination in Glass/Polyester Composites

Abstract

This article proposes an experimental study on the mode I interlaminar fracture of glass/polyester composites by using acoustic emission (AE) to analyze the damage evolution and evaluate the interlaminar performance of polymeric composites. A delamination process simulated with a double cantilever beam in opening mode (Mode I) coupled with an AE technique has been employed. The microscopic observation (scanning electron microscopy) is used to determine the correlation between different fracture mechanisms and their corresponding AE signal frequency content. Selected emissions are classified as matrix cracking, fiber breakage, or interface processes (fibermatrix debonding) based on their total power in defined frequency intervals of the spectral power density. A correlation was established between the mechanical energy release rate and the AE energy rate. Analysis in the frequency domain shows AE parameters are powerful indicators of the intensity of the damage.

Prediction of quasi-static delamination onset and growth in laminated composites by acoustic emission

“…In this study, in order to discriminate hit and noise signals some hardware and software filtration methods were used [15][16][17]. Waveform features such as rise time, duration and amplitude were involved in filtering of the AE data [18][19][20]. [21,22][Jianguo Yu, Paul Ziehl].…”

“…Paget [19] utilized the AE method to localization and identification of damage mechanisms that occurred in the carbon/epoxy plate under compression loading. Refahi et al [20] study delamination in glass/polyester composites under mode I loading condition using AE. They determine the initiation of delamination and interlaminar fracture toughness of the specimens.…”

Acoustic Emission-Based Methodology to Evaluate Delamination Crack Growth Under Quasi-static and Fatigue Loading Conditions

“…Some studies have used AE technique to investigate the delamination behavior under quasi-static loading condition [28][29][30][31][32]. Fotouhi and Ahmadi [33] investigate initiation of delamination in laminated composites under mixed-mode loading condition using AE technique.…”

Using Acoustic Emission to Evaluate Fracture Toughness Energy Release Rate (GI) at Mode I Delamination of Composite Materials

“…Microscopic behavior of fiber matrix interface microdamage is more difficult to be investigated, although it represents a major part of the delamination process. For monitoring microscopic events, Acoustic Emission (AE) is an appropriate tool (Refahi Oskouei & Ahmadi, 2010;Ndiaye et al, 2000;R'Mili et al, 2008;Cesari et al, 2007;Huguet et al, 2002). However, the interpretation of the signals and, hence, the evaluation of the damage stages is a major problem of the AE method.…”